1. Field of the Invention
The present invention relates to an apparatus for connecting one end of a shoe or boot to a ski which allows for lifting of the heel for skiing, particularly cross-country or mountaineer skiing.
2. Description of Relevant Materials and Background
Various ski binding apparatus are known for securing the front end of a ski boot onto a ski for use in mountaineer or cross-country skiing. Such apparatus allows for the lifting of the heel, in certain cases even the entire boot, during walking. These apparatus generally comprise a flexible and elastic flexion element which connects the front of the boot to the ski.
In certain types of binding apparatus of this type, such as that described in French Application No. 76,09945, retention to the ski is achieved by means of a frontward extension of the sole of the boot, which is molded together with the sole and is of unitary construction therewith. Other types of binding apparatus, such as described in French Patent Application No. 79,02513, the disclosure of which is hereby incorporated by reference, comprise a flexible and elastic element constituted by an intermediate element attached to the ski and on which the front of the boot is interlocked and latched.
In all of these apparatus, the tendency of the ski to remain on track is assured by the elasticity of the retention element in the binding which provides a force such that the ski tip remains in the track, e.g., by means of the elasticity of either the front edge of the sole or of the flexion element. The guidance of the ski along its original direction thus imposes a certain strain on the skier during the raising of his heel. This results in a consumption of energy during the entire lifting movement of the foot and leg, whereas pressure really need only be exerted at the end of the heel lifting movement, rather than throughout its entire extent. The initial lifting of the heel against a flexional resistance thus results in a needless waste of energy by the skier.